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udo-munk / z80pack

A Zilog Z80 and Intel 8080 systems emulation
MIT License
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Add MITS 88-SIO Rev. 1 to IMSAI machine #43

Closed udo-munk closed 5 years ago

udo-munk commented 6 years ago

Priority: medium Difficulty: easy

IMSAI didn't use I/O ports 0/1 so a MITS SIO can be plugged into the system. This allows to run the MITS BASIC interpreters also on the IMSAI machine, was done by original owners way back then too.

Don't know if it creates problems with the ESP port or a Web frontend, because 2 different SIO's are connected to one terminal. Might need conditional compiling for excluding it.

udo-munk commented 5 years ago

The IMSAI SIO occupies a port range of 16 bytes, from which only 5 ports have a function. A port scan on a real IMSAI 8080 machine with IMSAI SIO shows, that all 16 ports are active on input, so it is not possible to configure any other card in this I/O range. So this idea also won't be implemented in emulation, because I want it as realistic as possble.